Paper guide

ABSTRACT

A guide for use between two driving members of a web or sheet transport where one feeding member feeds the web at a velocity greater than the succeeding feeding member which receives the web. The guide permits a controlled transverse bend to develop in the web between the feeding members to accommodate various lengths of web before operation of the first feeding member is interrupted.

United States Patent [191 Brewitz [451 July 3,1973

1 1 PAPER GUIDE [75] inventor: George W. Brewitz, St. Paul, Minn.

[73] Assignee: Minnesota Mining and Manufacturing Company, St. Paul, Minn.

22 Filed: Jan. 3, 1912 21 Appl. No.: 214,761

[52] 11.8. CI 226/113, 226/118, 226/196 [51] Int. Cl B65h 23/04 [58] Field of Search 226/113, 118, 196,

[56] References Cited UNITED STATES PATENTS 1,898,850 2/1933 Papo 226/113 UX 2,569,364 9/1951 Zenner 226/196 X Primary Examiner-Richard A. Schacher Attorney-Alexander, Sell, Steldt & Delahunt [5 7] ABSTRACT A guide for use between two driving members of a web or sheet transport where one feeding member feeds the web at a velocity greater than the succeeding feeding member which receives the web. The guide permits a controlled transverse bend to develop in the web between the feeding members to accommodate various lengths of web before operation of the first feeding member is interrupted.

2 Claims, 2 Drawing Figures PAIENIEDJUL 3 ma 3.743.154

FIG. 1 FIG. 2

PAPER GUIDE This invention relates to a guide member in a web or sheet transport apparatus and more specifically to a guide member disposed between two feeding members which move the web at different speeds.

BACKGROUND OF THE INVENTION In numerous sheet transport devices a length of sheet material will be fed from a supply. This length of sheet material is moved at a constant speed from the supply and is fed around a bend, usually 180, to a second feeding member which may be a transport associated with a processor of one type or another. The processing transport generally moves the sheet at a slower speed than the first feeding member. As the length of the sheet exceeds the spacing between the sheet feeding members the sheet is caused to buckle or become wrinkled. Previous guides for avoiding a wrinkling of the sheet utilized a guide member which was pivoted and worked against a counterweight such that as the length of the sheet exceeded the spacing between the feeding members defined by the guide the guide could pivot out of its guide path against the counterweight. Alternative methods were to use a solenoid which after a predetermined length of sheet material was fed between the feeding means a pressure was exerted by the sheet to activate a solenoid which moved the guide member out of position permitting the sheet material to seek its own guiding path.

The present invention utilizes a simplified web guide which does not need to be pivotally mounted and needs no springs but yet accommodates sheets of various lengths and permits them to be folded in a predetermined regular manner by the guide.

SUMMARY OF THE INVENTION The guide of the present invention comprises means defining a first semicylindrical guide surface which receives the sheet material from the first web feed members and directs the free end of the web to a second slower feed member. A second semicylindrical guide surface is positioned adjacent the second feed member and extends toward the first member in a path offset from the path defined by the first guide surface. As a sheet is guided along the guide and engages the second slower feed member, the continued driving of the sheet by the first faster feed member places a compression in the sheet forcing it against the guide and the sheet conforms to the first and second guide surfaces. The offset between the surfaces intermediate the ends introduces a transverse bend in the sheet. This bend may then develop into a loop as the length of material fed by the first feed member increases. After the feeding of a predetermined length, the first feed means is stopped or the end of the sheet is reached. The sheet is then progressively drawn through the second feed member without any wrinkling or folding occuring in the sheet material.

The invention will be better understood after reading the following detailed description which refers to the accompanying drawing wherein:

FIG. 1 is a fragmentary perspective view of a sheet transport and cut-off mechanism utilizing a web guide constructed according to the present invention; and

FIG. 2 is a schematic view showing the operation of the web guide of the present invention.

Referring to the drawings, there is illustrated in FIG. 1 a web or sheet handling mechanism having a first web transporting member including a driven capstan 5 which is driven at a velocity by a motor 6 to feed a web 8 at a first speed, and a pressure roller 7 which urges the web 8 into contact with the capstan 5.

The first feed member feeds the web across a guide 9 and an anvil 10 beneath a cutting knife 11. The web 8 is then guided against the web guide, generally designated by the reference numeral 15. The web guide 15 directs the free end of the web into the nip of a second feeding member which, as illustrated, includes a large driven drum 16 which may be a heated drum for treating the web and a smaller pressure roller 17 urging the web into driving contact against the drum 16. The drum 16 is driven by a motor 18 at a velocity to feed the web at a second speed slower than the peripheral velocity of the drive roller 5 such that the web does not move as fast through the rollers 16 and 17 as between the rollers 5 and 7. Alternative to roller 17, the roller 16 may have a fixed shoe placed thereabout to contact the web and hold it against the drum 16 to afford development or some processing operation on the web.

These processors, because of the fact that the sheet or web material moves through them at a slower speed, and that the length of the sheet may vary, causes the sheet to necessarily double up or fold within the space between the web feeding means. This space or path between the feeding means never exceeds the length of the shortest web to be processed so that control of the web is maintained. The larger sheets need additional control over the intermediate portion of the sheet. In the sheet guide of the present invention the guide comprises a wire form member or sheet metal part which is formed to define a first semicylindrical guide surface 20, which arcuate surface is formed about an axis extending generally parallel to the axis of the feed rollers 5 and 7. The semicylindrical surface 20 engages the web 8 as it is driven by the first feeding means and directs the same toward the nip of the second feeding means. The first surface 20 extends from the position adjacent the first feeding member toward the second feeding member through an arc of approximately The guide 15 is formed with a second semicylindrical surface 21 which has a first end portion 22 disposed adjacent the second feeding member and extends in an arcuate path toward the first feeding member but the surface 21 is offset from the path of the first guide surface 20 away from the feeding members. The second guide surface 21 must have a length sufficient to contact the free end of the sheet as it is initially directed from the first guide surface 20 toward the second feeding member 16 andl7. The surface may be discontinuous to allow a spacing between its opposite end and the adjacent end of the first surface 20. But, as shown in the drawing, the guide 15 is formed of one continuous sheet and an offset or shoulder 23 connects the adjacent ends of the guide surfaces.

Referring now to FIG. 1 you will see that the web 8 is guided along the first surface 20 and has been directed into the nip between the rollers 16 and 17 of the second feeding means.

In FIG. 2, the web 8 is shown in dotted lines to illustrate the next position taken by the web as the first feeding member 5 and 7 feed an extent of web material, exceeding the spacing between the feeding means around the bend or path. The web 8 has begun to conform to the second guide surface 21 and to develop a transverse bend at the edge '25 of the first guide surface 20. This bend at the edge 25 will cause an even loop to develop in the web such that, as the first feeding member continues to feed the web, a loop will develop in the web such as shown in the solid line position in FIG. 2.

The second guide surface 21 may terminate at a position about 45 from the edge 22 rather than join the surface 20 as shown. This configuration would permit the loop in the web to develop to the right of the guide surface 21 rather than to the left as shown in FIG. 2. This alternative depends on whether or not the space is available to the right or to the left of the guide to accommodate the loop in the web as the various lengths are fed between the two feeding members, The length of the web or sheet is thus dependent on the availability of space.

Having thus described the present invention with reference to the preferred embodiment shown in the drawings, it will be appreciated that further modifications may be made without departing from the spirit of this invention.

What is claimed is:

1. In a web transport apparatus having a first web feeding member for moving various lengths of web at a first speed and a spaced second web feeding member for moving the web at a second speed slower than said first speed, said first member and second member being spaced less than the shortest length of web to be moved by said members and a guide forming a guide path between said first and second members for directing the web from the first to the second member, said guide comprising means defining a first semicylindrical guide surface positioned for receiving a web fed from said first member and for directing the free end thereof along a first continuous portion of a guide path toward the second member through an arc of approximately said first surface terminating in a position spaced from said second member, and means defining a second semicylindrical guide surface positioned to continue the guide path and to engage the same side of the web as the first surface with one edge adjacent said second member and extending toward the first feeding member with the other edge spaced radially in relationship to the first surface for defining a second portion of the guide path offset away from the portion of said first surface between said feeding members whereby a web being driven by said first and second feeding members will be placed in said first portion and when subject to compression will be deflected to contact said second surface along an extent thereof such that the offset relationship will place a transversely extending roll in a web which exceeds the distance between said first and second feeding members along the guide path defined by the guide surfaces.

2. A web transport according to claim 1 wherein said means defining said guiding surfaces is a single member having a first semicylindrical portion joined by an angularly positioned portion to a second semicylindrical portion, the axes of said semicylindrical portions being substantially parallel. 

1. In a web transport apparatus having a first web feeding member for moving various lengths of web at a first speed and a spaced second web feeding member for moving the web at a second speed slower than said first speed, said first member and second member being spaced less than the shortest length of web to be moved by said members and a guide forming a guide path between said first and second members for directing the web from the first to the second member, said guide comprising means defining a first semicylindrical guide surface positioned for receiving a web fed from said first member and for directing the free end thereof along a first continuous portion of a guide path toward the second member through an arc of approximately 90*, said first surface terminating in a position spaced from said second member, and means defining a second semicylindrical guide surface positioned to continue the guide path and to engage the same side of the web as the first surface with one edge adjacent said second member and extending toward the first feeding member with the other edge spaced radially in relationship to the first surface for defining a second portion of the guide path offset away from the portion of said first surface between said feeding members whereby a web being driven by said first and second feeding members will be placed in said first portion and when subject to compression will be deflected to contact said second surface along an extent thereof such that the offset relationship will place a transversely extending roll in a web which exceeds the distance between said first and second feeding members along the guide path defined by the guide surfaces.
 2. A web transport according to claim 1 wherein said means defining said guiding surfaces is a single member having a first semicylindrical portion joined by an angularly positioned portion to a second semicylindrical portion, the axes of said semicylindrical portions being substantially parallel. 